D.P. GUPTA, Preetima Bajpai and, Sanjeev Kumar Jha Solutions for Chapter: Solid State, Exercise 2: Exercise 2

Argon crystallizes in a structure in which the atoms are located at the positions $(0, 0, 0), \left(0, \frac{1}{2}, \frac{1}{2}\right), \left(\frac{1}{2}, 0, \frac{1}{2}\right)$ and $\left(\frac{1}{2}, \frac{1}{2}, 0\right)$. The unit cell is

Consider the radii $0.095 \mathrm{nm} \left({\mathrm{Na}}^{+}\right), 0.181 \mathrm{nm} \left({\mathrm{Cl}}^{-}\right),$ $0.074 \mathrm{nm} \left({\mathrm{Zn}}^{2+}\right), 0.184 \mathrm{nm} \left({\mathrm{S}}^{2-}\right), 0.068 \mathrm{nm} \left({\mathrm{Ti}}^{4+}\right),$ $0.140 \mathrm{nm} \left({\mathrm{O}}^{2-}\right) \text{and} 0.169 \mathrm{nm} \left({\mathrm{Cs}}^{+}\right).$ Choose the correct option from the following. (Use radius ratio rules)

The non-stoichiometric compound, ${\mathrm{Fe}}_{0.94}\mathrm{O}$ is formed when $\mathrm{x}\%$ of ${\mathrm{Fe}}^{2+}$ ions are replaced, such that each ${\mathrm{Fe}}^{2+}$ ion is replaced by $2/3 {\mathrm{Fe}}^{3+}$ ions. $\mathrm{x}$ is

$\mathrm{NaCl}$ is doped with $2\times {10}^{-3}$ mole $\%$ of ${\mathrm{SrCl}}_2$. The concentration of cation vacancies is

${\mathrm{NH}}_4\mathrm{Cl}$ crystallises in a BCC lattice with the edge length of the unit cell equal to $387 \mathrm{pm}$. If the radius of the ${\mathrm{Cl}}^{-}$ ion is $181 \mathrm{pm}$, the radius of the ${{\mathrm{NH}}_4}^{+}$ ions is:

The ratio of inner planar distances of three types of planes $\left({\mathrm{d}}_{100}, {\mathrm{d}}_{110}, {\mathrm{d}}_{111}\right)$ for simple cubic lattice is

What type of crystal defect is indicated in the arrangement below? (Consider it a closed lattice where ${\mathrm{Na}}^{+} \text{and} {\mathrm{Cl}}^{-}$ are joined together and $\square$ represents a void)

$$\begin{gathered} {\mathrm{Na}}^{+}-{\mathrm{Cl}}^{-}-{\mathrm{Na}}^{+}-{\mathrm{Cl}}^{-} - {\mathrm{Na}}^{+}-{\mathrm{Cl}}^{-} \\ {\mathrm{Cl}}^{-}- \square - {\mathrm{Cl}}^{-}- {\mathrm{Na}}^{+ }- \square - {\mathrm{Na}}^{+} \\ {\mathrm{Na}}^{+}-{\mathrm{Cl}}^{-} -\square - {\mathrm{Cl}}^{-} - {\mathrm{Na}}^{+}-{\mathrm{Cl}}^{-} \\ {\mathrm{Cl}}^{-} - {\mathrm{Na}}^{+}- {\mathrm{Cl}}^{-}- {\mathrm{Na}}^{+}-\square - {\mathrm{Na}}^{+} \end{gathered}$$

A metal has $\mathrm{bcc}$ structure and the edge length of its unit cell is $3.04 \mathrm{\AA }$. The volume of the unit cell in ${\mathrm{cm}}^3$ will be